.box{
    width: 350px;
    margin: 0 auto;
    margin-top: 100px;
    text-align: center;
}
.header{
    display: flex;
    align-items: center;
}
.header .add {
    width: 200px;
    height: 20px;
}
.header input{
    width: 20px;
    height: 20px;
}
.header button{
    margin-left: 20px;
}
main {
    width: 350px;
    margin: 0 auto;
    font-size: 20px;
    margin-top: 20px;
}
.list{
    display: flex;
    align-items: center;
    height: 30px;
    border: 1px solid gray;
}
.list input{
    width: 90%;
    margin: 0 auto;
}
.list div{
    height: 30px;
    line-height: 30px;
    display: flex;
    align-items: center;

}
.list div input{
    width: 20px;
    height: 20px;
}
.list div div{
    width: 210px;
}
.list div button {
    height: 25px;
    margin-left: 10px;
}